高迁移率蛋白-1在脓毒症大鼠肺中的表达

Expression of high mobility group 1 protein in lung during sepsis in rats

目的探讨脓毒症大鼠肺组织中高迁移率蛋白-1(HMG-1)的表达。方法 50只SD 大鼠随机分为对照组(10只)和试验组(40只),使用逆转录-聚合酶链反应(RT-PCR)法检测肺与空肠组织HMG-1 mRNA的表达,采用Western blot法检测HMG-1蛋白的表达。结果试验组肺、空肠组织中HMG-1 mRNA表达量明显高于对照组(0．866±0．026 vs 0．232±0．009和0．859±0．053 vs 0．227±0．025,P<0．05),试验组肺组织中HMG-1蛋白表达量明显高于对照组(1．060±0．036 vs 0．360±0．006,P<0．05),但各亚组之间差异无统计学意义(P>0．05);空肠组织中HMG-1蛋白表达量与对照组比较,差异无统计学意义(P>0．05)。结论 HMG-1可能是炎症反应的重要介质,在炎症反应的持续发展过程中起一定作用。

Objective To investigate the expression of high mobility group （HMG）-1 protein and mRNA in sepsis rat. Methods By using a sepsis model by cecal ligation and puncture, 50 male SD rats were randomly divided into two groups：normal control （ n = 10）, CLP groups which were subdivided into 24, 48, 72 and 96·h post-CLP subgroups （n = 10 in each）. At serial time points in each group, animals were sacrificed, and blood as tissue as samples from the lung and intestine were harvested to measure HMG-1 and TNF-α mRNA expression by the reverse transcription polymerase chain reaction and HMG- 1 protein expression by immunoblot with β-actin as an internal standard. Results HMG-1 mRNA levels were significantly increased in lung and intestine tissues during 24-96 h after CLP （0. 866±0.026 vs 0. 232 ± 0. 009 vs 0. 859 ± 0. 053 vs 0. 227 ±0. 025, P 〈 0.05 ）, and the protein expression levels also significantly increased in lung compared to the control （ 1. 060 ±0. 036 vs 0. 360 ± 0. 006, P 〈 0.05）. TNF-α mRNA levels were significantly increased in lung and intestine tissues during the first 24 h and returned to the control level promptly. Conclusion HMG-1 may be a key factor in the development of excessive inflammatory response.